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Analyzing the Effectiveness of Argumentation Program to Conceptualize the Concept of Natural Selection for Elementary Science-Gifted Students (초등과학영재들의 자연선택 개념 형성을 위한 논변활동 효과 분석)

  • Park, Chuljin;Cha, Heeyoung
    • Journal of The Korean Association For Science Education
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    • v.36 no.4
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    • pp.591-606
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    • 2016
  • The purpose of this study is to develop the argumentation program to build scientific concepts on natural selection for science-gifted elementary students and to know how to implement this program. For this study, nine key concepts about natural selection such as the overproduction of offspring, limited resources, population stability, competition, variation, heredity of variation, differential survival, change of the population and speciation were selected through the literature study. The programs were developed by learning cycle instructional model. Argument writings and discourses have been collected, analyzed and compared before and after the program. Two questionnaires to compare pre and post concept change consist of multiple choice questionnaire and open-ended response question were developed and applied to 19 science-gifted elementary students. Sufficiency of the explanation and conceptual quality of the explanation were used to assess the quality of their arguments before and after the program. Discourse and visual models collected from the highest and lowest group about score improvement were compared. The scores of the gifted statistically improved significantly in multiple choice questionnaire. Students' alternative conceptions about natural selection at the beginning of the program decreased and changed scientifically after the program. Visual models drawn by the students supported the results as well. This study asserts that elementary science-gifted students are able to explain evolutionary perspectives about organism change and use the key concepts of natural selection. The study means that evolutionary perspective is possible to be reflected in elementary science curriculum for the gifted.

Retention of CAD/CAM Metal Copings Cemented on Short Titanium Abutments with Different Cements (짧은 티타늄 지대주에 합착된 CAD/CAM 금속 코핑의 시멘트 종류에 따른 유지력 비교)

  • Kim, Hyo-Jung;Song, Eun-Young;Yoon, Ji-Young;Lee, Si-Ho;Lee, Yong-Keun;Oh, Nam-Sik
    • Journal of Dental Rehabilitation and Applied Science
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    • v.28 no.2
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    • pp.119-126
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    • 2012
  • State of problem: Cement-retained implant-supported prostheses are routinely used in dentistry. The use of high strength cements has become more popular with the increasing confidence in the stability of the implant-abutment screw connection and the high survival rates of osseointegrated implants. No clinical data on retention of metal copings using CAD/CAM. To evaluate retention of metal copings using CAD/CAM system bonded to short titanium abutment with four different cements and compare retentive strength of metal copings with sandblasting or without sandblasting before cementation. Forty titanium abutment blocks were fabricated and divided into 4 groups of 10 samples each. Forty metal copings with occlusal hole to allow for retention testing were fabricated using CAD/CAM technology. The four cements were Fujicem(Fuji, Japan), Maxcem Elite(Kerr, USA), Panavia F2.0(Kurarary, Japan) and Superbond C&B(Sunmedical, Japan). The copings were cemented on the titanium abutment according to manufacture's recommendation. All samples were stored for 24h at 37oC in 100% humidity and tested for retention using universal testing machine(Instron) at a crosshead speed of 1.0mm/min. Force at retentive failure was recorded in Newton. The mode of failure was also recorded. Means and standard deviations of loads at failure were analyzed using ANOVA and Paired t-test. Statistical significance was set at P<0.05. Panavia F2.0 provided significantly higher retentive strength than Fujicem, Maxcem Elite(P<0.05). Sandblasting significantly increased bond strength(P<0.05). The mode of failure was cement remaining principally on metal copings. Within the limitation of this study, Panavia F2.0 showed significantly stronger retentive strength than Fujicem, Maxcem Elite(p<0.05). The Ranking order of the cements to retain the copings was Panavia F2.0, Fujicem = Maxcem Elite. Sandblasting significantly increased bond strength(P<0.05). The retentive strength of metal copings on implant abutment were influenced by surface roughness and type of cements.

Can Lufthansa Successfully Limit its Liability to the Families of the Victims of Germanwings flight 9525 Under the Montreal Convention?

  • Gipson, Ronnie R. Jr.
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.2
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    • pp.279-310
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    • 2015
  • The Montreal Convention is an agreement that governs the liability of air carriers for injury and death to passengers travelling internationally by air. The Montreal Convention serves as the exclusive legal framework for victims and survivors seeking compensation for injuries or death arising from accidents involving international air travel. The Montreal Convention sets monetary liability caps on damages in order to promote the financial stability of the international airline transport industry and protect the industry from exorbitant damages awards in courts that would inevitably bankrupt an airline. The Convention allows a litigant suing under the Convention to avoid the liability caps in instances where the airline's culpability for the injury or death is the direct result of negligence, another wrongful act, or an omission of the airline or its agents. The Montreal Convention identifies specific locations as appropriate venues to advance claims for litigants seeking compensation. These venues are closely tied to either the carrier's business operations or the passenger's domicile. In March 2015, in an act of suicide stemming from reactive depression, the co-pilot of Germanwings flight 9525 intentionally crashed the aircraft into the French Alps killing the passengers and the remaining crew. Subsequent to the crash, there were media reports that Lufthansa made varying settlement offers to families of the passengers who died aboard the flight ranging from $8,300 USD to $4.5 Million USD depending on the passengers' citizenship. The unverified offers by Lufthansa prompted outcries from the families of the decedent passengers that they would institute suit against the airline in a more plaintiff friendly jurisdiction such as the United States. The first part of this article accomplishes two goals. First, it examines the Montreal Convention's venue requirement along with an overview of the recoverable damages from countries comprising the citizenship of the passengers who were not American. The intentional crash of Germanwings flight 9525 by its First Officer encompasses the possibility that Lufthansa may be exposed to unlimited compensatory damages beyond the liability caps contained in the Convention. The second part of this article explores the application of the Convention's liability limits to the Germanwings flight to demonstrate that the likelihood of escaping the liability limits is slim.

Effects of Arginine Vasopressin(AVP) Infusion on the Patients with Catecholamine-dependent Septic Shock (카테콜아민계 승압제를 투여중인 패혈성 쇼크 환자에서 아르기닌 바소프레신(AVP)의 효과)

  • Sheen, Seung Soo;Lim, Seung Guan;Jo, Sook Kyoung;Song, Kyoung Eun;Lee, Hyoung No;Oh, Yoon Jung;Park, Kwang Joo;Hwang, Sung Chul
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.5
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    • pp.506-515
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    • 2003
  • Background : A decreased level of serum arginine vasopressin(AVP) and an increased sensitivity to an exogenous AVP is expected in patients with septic shock who often require a high infusion rate of catecholamines. The goal of the study was to determine whether an exogenous AVP infusion to the patients with septic shock would achieve a significant decrement in infusion rate of catecholamine vasopressors while maintaining hemodynamic stability and adequate urine output. Method : Eight patients with septic shock who require a high infusion rate of norepinephrine had received a trial of 4-hour AVP infusion with simultaneous titration of norepinephrine. Hemodynamic parameters and urine output were monitored during the AVP infusion and the monitoring continued up to 4 hours after the AVP infusion had stopped. Results : Mean arterial pressure showed no significant changes during the study period(p=0.197). Norepinephrine infusion rate significantly decreased with concurrent AVP administration(p=0.001). However, beneficial effects had disappeared after the AVP infusion was stopped. In addition, hourly urine output showed no significant changes throughout the trials(p=0.093). Conclusion : Concurrent AVP infusion achieved the catecholamine vasopressor sparing effect in the septic shock patients, but there was no evidence of the improvement of renal function. Further study may be indicated to determine whether AVP infusion would provide an organ-protective effect to the septic shock patients.

Evaluation of Cleanness and Physical Properties of W/O Microemulsion (W/O Microemulsion 세정제의 물성 및 세정성 평가)

  • Lee, Myung Jin;Han, Ji Won;Lee, Ho Yeol;Han, Sang Won;Bae, Jae Heum;Park, Byeong Deog
    • Korean Chemical Engineering Research
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    • v.40 no.6
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    • pp.769-777
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    • 2002
  • Using four components - nonionic surfactants, water, hydrocarbon oil and an alcohol as cosurfactant, 12 types of cleaning agents were prepared, and their physical properties such as surface tension, viscosity, electroconductivity and phase stability were measured. As the formulated cleaning agents have low surface tensions(30.5-31.1 dyne/cm) and low viscosities (1.6-7.2 c.p.), they are satisfied with the general physical properties of water-in-oil(W/O) microemulsions for their industrial use. They showed a tendency that their temperature range for stable one-phase microemulsion decreased in accordance with the increase of alcohol/surfactant(A/S) ratio in the formulations. However, the temperature range of one-phase microemulsion was much more affected by hydrophilic lipophillic balance(HLB) value of the nonionic surfactant which increased its temperature range and it increased in accordance with the higher HLB value in the formulations. And the maximum content of water which can keep stable one-phase W/O microemulsion was measured at each sample. In addition, their temperature range for stable one-phase microemulsion was also measured. It was confirmed that the selection of surfactant type was very important for formulating a cleaning agent, since the W/O microemulsion system with the nonionic surfactant of the lower HLB value showed better cleaning efficacy that of the higher HLB value for abietic acid as a soil, which was used for preparing a rosin-type flux. In the formulated cleaning agents with the increase of A/S ratio in the formulations, however, there was no significant difference in cleaning efficacy. It was investigated that the differences of their cleaning efficacy was affected by the change of the condition of temperature and sonicating frequency as important factors in the industrial cleaning. That is, the higher, their cleaning temperature and the lower, their sonicating frequency, the more increased, their cleaning efficacy. Furthermore, using optical instruments like UV/Visable Spectrophotometer and FT-IR Spectrometer, their cleaning efficacy for abietic acid was measured. The removal of soil from the contaminated rinse water was measured by gravity separation method in the rinse bath. As a result, the cleaning agent system having the nonionic surfactant of HLB value 6.4 showed over 85% water-oil separation efficacy at over $25^{\circ}C$. Therefore, it was demonstrated in this work that the formulating cleaning agents were very effective for cleaning and economical in the possible introduction of water recycling system.

Determinants of Demand for Long-Term Care (장기요양서비스 수요의 결정요인)

  • Chung, Wankyo
    • KDI Journal of Economic Policy
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    • v.31 no.1
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    • pp.139-167
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    • 2009
  • A new public insurance for long-term care was introduced in July 2008 to provide for the rising demand for long-term care as the population is aging rapidly. The demand for long-term care is expected to rise further because more and more elderly are living alone or in households with only other elderly, such as his/her spouse, without informal care of their adult children. Even when the elderly are living together with their adult children, daughters and daughters in law, once the main informal care-givers, are not available because they choose to become economically active and work more over time. Experiences of countries such as Japan and Germany with similar public long-term care insurance scheme highlight the importance of detailed analysis on the demand for long-term care for the financial stability of the insurance scheme. Countries which had underestimated the demand for long-term care at the time of adopting the scheme went through financial instability of insurance schemes. This study analyzes the determinants of the demand for long-term care using data from the second demonstration project (April 2006~April 2007) of the long-term care insurance scheme for the elderly in Korea. Taking full advantage of detailed data on the long-term care, this paper analyzes the eligibility for the long-term care insurance scheme and its use. According to study results, even when common diseases among the elderly such as cancer, diabetes, arthritis, dementia, hypertension, etc. are controlled together with other individual and socioeconomic factors, limitations the elderly are faced with in their twelve activities of daily living significantly affect the eligibility for the Korean Long-term Care Insurance Scheme. This means that limitations in daily living activities are more critical than common diseases among the elderly are to the eligibility for the Korean Long-term Care Insurance Scheme. Bathing and toileting problems have been found to be the most important factor affecting the eligibility for the insurance scheme, followed by eating, dressing and moving around inside the house. Moreover, the choices of whether to use long-term care and which to use between home care and institutional care are found to be significantly influenced by health status and various socioeconomic factors of the elderly. In particular, those with more limitations in daily living activities and the female elderly are more likely to use long-term care and institutional care rather than home care. As for home care users, those living alone or with adult children and those with monthly household income of more than 500,000 won are more likely to use home care. Most importantly, even when the monthly household income of the elderly is controlled, the elderly recipients of the National Basic Living Security, who are not charged for long-term care, are more likely to choose home care. This implies that price as well as income is a critical factor for the decision to use long-term care. Further study on the duration of long-term care use will surely enhance the long-term care policy, when panel data is available for simultaneous analysis of the likelihood of long-term care use and its use duration.

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An Analysis of Value and Personality for the Crippled Person's Psychological Rehabilitation (지체장애인의 심리적 재활을 위한 성격 및 가치관 분석)

  • Eum Ik-Gon;Kim Kyu-Soo
    • The Journal of Korean Physical Therapy
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    • v.4 no.1
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    • pp.79-93
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    • 1992
  • This study is search for analyzed the primary factor of psychological characters of crippled person toward psychological rehabilitation that is the most foundmental to all rehabilitation for a crippled person. The research is, make a comparative analyze to personality character, value character, and motion, and then examined the relation of among then, by applies to high school's crippled students. First. in the personality character aspect, a group of crippled student's is shown that the factor of family relations is lack harmony than normal group, that is, shown up that a parents and family members is oversensitiveness to crippled person, So sometimes they overprotectiveness, unconcered, and not accept it is. Also, in the factor of confrontability aspect, a group of crippled person's average is shown to high as compared with normal group, and then, it shown that they are irresponsible, have a weak self-control, and show a marked trend toward self-control. This is means that crippled person have scruples about psychological and social adaptation. But friendship, adaptability, cheefulness. and emotonal stability is shown no difference with normal person. Accordingly, in the personality aspect, the falter of family-relation and confrontability can be know that the object of psychological rehabilitation. Second, in the sence of value aspect, crippled students is show that the average score had higher than normal group toward the factor of variety, therefor we can know that they have purpose to more pursur of variety in the living. This is consideration that a raise from the limited of social contact chance and badly informed and experience. Also, the factor of purpose-intention is shown that crippled students had low non than normal group, then, that means that they have a weak will toward cope with various problems in daily living. Crippled student is, in contrast to lacked fixed purpose with self-living, and also insufficient tring to accomplish their objects. Third, crippled students motion shown that related to low level of personality character and a sence of value factor. Daily living activity is show that related to the factors of confrontability and cheerfulness. This means that rehabilitation service given a change to confrontability and cheerfulness that can be effect is related. And the activity of home is related with confrontability, psychological rehabilitation for the change of activity is can say that it should be contribute to strengthen toward responsibility and self-control from self-central to intention at rho others. Fourth, the relation between an motion and a value of crippled student is shown low level of regulations that can be ignore. In sum, in the rehabilitation of crippled person, hereafter, a study subject is if which search to character factor and to find out effect inter-factors within the the factor of psychological rehabilitation as medical, occupational, social rehabilitation, then probably more effective development toward rehabilitation programs. Conseguently, hereafter for the crippled person's rehabilitaton, the study should be rquirement for establish a character and factors each filed of rehabilitation. The study sibject toward crippled person's rehabilitation for the fature is search for character factor toward medical. occupational, and social rehabilitation. and find out inter-relation among then like as search of this study for psychological rehabilitation. For the rehabilitation of crippled person, if is not preceding of study like this, it ought to be difficult to creation service as well as development to effective program.

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The Development of Quality Assurance Program for CyberKnife (사이버나이프의 품질관리 절차서 개발)

  • Jang, Ji-Sun;Kang, Young-Nam;Shin, Dong-Oh;Kim, Moon-Chan;Yoon, Sei-Chul;Choi, Ihl-Bohng;Kim, Mi-Sook;Cho, Chul-Koo;Yoo, Seong-Yul;Kwon, Soo-Il;Lee, Dong-Han
    • Radiation Oncology Journal
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    • v.24 no.3
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    • pp.185-191
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    • 2006
  • [ $\underline{Purpose}$ ]: Standardization quality assurance (QA) program of CyberKnife for suitable circumstances in Korea has not been established. In this research, we investigated the development of QA program for CyberKnife and evaluation of the feasibility under applications. $\underline{Materials\;and\;Methods}$: Considering the feature of constitution for systems and the therapeutic methodology of CyberKnife, the list of quality control (QC) was established and divided dependent on the each period of operations. And then all these developed QC lists were categorized into three groups such as basic QC, delivery specific QC, and patient specific QC based on the each purpose of QA. In order to verify the validity of the established QA program, this QC lists was applied to two CyberKnife centers. The acceptable tolerance was based on the undertaking inspection list from the CyberKnife manufacturer and the QC results during last three years of two CyberKnife centers in Korea. The acquired measurement results were evaluated for the analysis of the current QA status and the verification of the propriety for the developed QA program. $\underline{Results}$: The current QA status of two CyberKnife centers was evaluated from the accuracy of all measurements in relation with application of the established QA program. Each measurement result was verified having a good agreement within the acceptable tolerance limit of the developed QA program. $\underline{Conclusion}$: It is considered that the developed QA program in this research could be established the standardization of QC methods for CyberKnife and confirmed the accuracy and stability for the image-guided stereotactic radiotherapy.

Characteristics of alkaline and acid phosphatase in Spirometra erinacei (만손열두조충(Spirometra erinacei)에서 알칼리성과 산성 인산효소의 특성)

  • 곽기훈;김창환
    • Parasites, Hosts and Diseases
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    • v.34 no.1
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    • pp.69-78
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    • 1996
  • This study was done to investigate the enzyme-histochemical localization and characteristics of alkaline and acid phosphatase related with metabolism in sparganum and adult of Spirometrn erinacei. By the enzyme-histochemical assay, the alkaline and acid phosphatases were localized in the tegument and subtegumental musculature of sparganum and adult, but not in the parenchyma. The activities of alkaline phosphatase were stronger in the tegument than in the subtegumental musculature, and activities of acid phosphatase were stronger in the tegument of adults than those of sparganum. The 2 isozymes of alkaline and acid phosphatases were separated from s-sparganum (from snake) and r-sparganum (from experimentaly infected rats) respectively but 4 isozymes of Alp and 3 isoxymes of Acp were separated from adult worms by electrophoresis. In isogyme Alp, the 661)a was the common isozyme, but 130 kDa isozyme of Acp was the common isozyme in spargana and adult worms. By isoelectrofocusing, 4 isozymes (PI 7.9, 7.7, 6.5 and 6.3) and 2 isozymes (PI 7.9 and 7.7) of alkaline phosphatase were separated from adults and spargana respectively. In the stability against heat, activity of alkaline phosphatase was denatured perfectly after heating at 90℃ for 40 seconds. The optimum pH and temperature for activity of alkaline phosphatase were about pH 10 and 50℃, respectively. The maximum activity (unit) of alkaline phosphatase was 22.0 in s- sparganum,25.0 in r-sparganum and 215.0 in adult worms, so that the maximum activity was revealed higher in adults than spargana. As the result from above, we observed that alkaline and acid phosphatases were functioned mainly in the tegument and subtegumental musculature , and the isoxymes of phosphatase were activated differently according to habitat of the parasites. The spargana and adult worms carry out the pafasitism by adapting thenlselves to parasitic circumstance loth these emxymes.

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Localization and characteristics of lactate and palate dehydrogenase in the sparganum and adult worm of Spirometra erinacei (만손열두조충에서 젖산탈수소효소와 말산탈수소효소의 분포와 특징)

  • Gwak, Gi-Hun;Jeon, Eun-U;Kim, Chang-Hwan
    • Parasites, Hosts and Diseases
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    • v.34 no.1
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    • pp.59-68
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    • 1996
  • This study investigated the enzyme histochemical localization and characteristics of lactate (LDH) and malate dehydrogenase (MDH) related with the oxidation-reduction metabolism in the sparganum and adult of 5. erinacei. By enzyme histochemical assay, activity of LDH was strong in the tegument and subtegumental muscle layers of the adult and sparganum. Activity of MDH was strong in the tegument of the sparganum and subtegumental muscle layers of the adult. However it was weak in the tegument of the adult. By electrophoresis, 45 kDa band was major and common in LDH of adults and spargana. The 150 kDa molecule was the major and common band in MDH of adults and r -spargana (from experimentally infected rats) . By isoelectrofocusing, isoelectric points (Pl) or 4 MDH isogyme from adult worm were 6.0.6.5, 6.7 and 7.1, respectively. Pl 6.0 was the major band. The active range of pH for MDH was about pH 6-8 and the optimum pH was pH 7 The effective temperature on the MDH was about $30^{\circ}C$$50^{\circ}C$ and the optimum temperature was about 40℃ in spargana md adult worm. In the stability against heat, when MDH was heated at 85℃ for 10 seconds, the activity was denatured perfectly. Maximum activity or MDH was 19.4 unit in the s-sparganum (from snakes), 24.5 unit in the r-sparganum (from rats) and 108.0 unit in the adult worm. The maximum activity was higher in adults than in spargana. The present result showed us that the nutrients absorbed through the tegument were transferred into inner tissues and were utilized as the source of metabolism. According to the habitat of the parasite, the isozymes of LDH and MDH are activated differently, and by this different activation the sparganum and adult can adapt themselves to parasitic circumstances.

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